The Engrammeter (depleted) is an item given to the player by Kharshai to collect Mahjarrat Memories, charged by 500 Divine memories of Vibrant or higher. It is used in the Mahjarrat Memories miniquest, starting out depleted but becoming charged when memories are collected. When players ask about the engrammeter, Kharshai will admit that it is the strange chest that held his memory gem from Koschei's Troubles, recycled for use in containing other memories.
After the player brings all 15 memories to Kharshai, he will state that the Engrammeter might be useful on Freneskae if the player is ever able to go there. As such, a fully charged Engrammeter will become a Distorted engrammeter, but will provide some damage reduction while on Freneskae. This also rewards the player with 25,000 Divination experience.
Trying to operate the charged engrammeter at Port Khazard or the Fight Arena will not give you the usual message when there is no memory to be found, but instead your character will say "Nothing here. Khazard must be too young to have left a memory." Likewise, using it at Zamorak's camp from the Battle of Lumbridge will produce "Nothing here. It must not work on gods or half-Mahjarrat."
Note that the Engrammeter can only hold up to 500 memories. Also, the engrammeter cannot be recharged until each memory is brought to Kharshai.